Final answer:
To make 36 cups of fruit punch, you will need 45 cups of apple juice.
Step-by-step explanation:
To find the number of cups of apple juice needed, you can set up a proportion using the given ratio of apple juice to pineapple juice.
5 cups of apple juice / 4 cups of pineapple juice = x cups of apple juice / 36 cups of fruit punch
Cross multiply and solve for x:
5 * 36 = 4 * x
x = 45
Therefore, you will need 45 cups of apple juice to make 36 cups of fruit punch.